A surge protector is an appliance or device designed to protect electrical devices from voltage spikes.
A surge protection device mounted on a residential circuit breaker panel.
Many power strips have basic surge protection built in; these are typically clearly labeled as such. However, in unregulated countries there are power strips labelled as "surge" or "spike" protectors that only have a capacitor or RFI circuit (or nothing) that do not provide true (or any) spike protection.